Asynchronous JavaScript And XML, or its acronym Ajax (Pronounced A-JAX), is a web development technique for creating interactive web applications. The intent is to shift a great deal of interaction to the web surfer's computer, exchanging data with the server behind the scenes, so that the entire web page does not have to be reloaded each time the user makes a change. This is meant to increase the web page's interactivity, speed, and usability.

ASP.NET AJAX is a free framework for quickly creating a new generation of more efficient, more interactive and highly-personalized Web experiences that work across all the most popular browsers.

AJAX or Asynchronous JavaScript and XML is a term describing a web development technique for creating interactive web applications using a combination of: * HTML (or XHTML) and Cascading Style Sheets for presenting information* Document Object Model, JavaScript to dynamically display and interact with the information presented* XML, XSLT and the XMLHttpRequest object to interchange and manipulate data asynchronously with the web server .